Search results for "lake metabolism"
showing 4 items of 4 documents
Influence of littoral periphyton on whole-lake metabolism relates to littoral vegetation in humic lakes
2017
The role of littoral habitats in lake metabolism has been underrated, especially in humic lakes, based on an assumption of low benthic primary production (PP) due to low light penetration into water. This assumption has been challenged by recent recognition of littoral epiphyton dominance of whole-lake PP in a small highly humic lake and of epiphyton as an important basal food source for humic lake biota. However, as these studies have mostly concerned single lakes, there is a need to test their wider generality. We studied the whole-lake PP and community respiration (CR) in eight small humic lakes in southern Finland during July 2015 using 14 C incorporation to measure pelagic PP and the c…
Ecosystem responses to increased organic carbon concentration: comparing results based on long-term monitoring and whole-lake experimentation
2019
Recent increases in terrestrial dissolved organic carbon (DOC) concentrations in northern inland waters have many ecological consequences. We examined available data on carbon cycles and food webs of 2 boreal headwater lakes in southern Finland. Basic limnology and catchment characteristics of a pristine lake, Valkea-Kotinen (VK), were monitored over the past 25 years while the lake has undergone browning and DOC increased from similar to 11 to 13 mg L-1. Pronounced changes in the early 2000s represent a regime shift in DOC concentration and color. Lake Alinen Mustajarvi (AM) was manipulated for 2 years by additions of labile DOC (cane sugar), raising the DOC concentration from similar to 1…
Influence of littoral periphyton on whole-lake metabolism relates to littoral vegetation in humic lakes
2017
The role of littoral habitats in lake metabolism has been underrated, especially in humic lakes, based on an assumption of low benthic primary production (PP) due to low light penetration into water. This assumption has been challenged by recent recognition of littoral epiphyton dominance of whole-lake PP in a small highly humic lake and of epiphyton as an important basal food source for humic lake biota. However, as these studies have mostly concerned single lakes, there is a need to test their wider generality. We studied the whole-lake PP and community respiration (CR) in eight small humic lakes in southern Finland during July 2015 using 14C incorporation to measure pelagic PP and the ch…
Accounting for littoral primary production by periphyton shifts a highly humic boreal lake towards net autotrophy
2016
1. The prevailing view that many humic lakes are net heterotrophic is commonly based on pelagicmeasurements alone. Poor light conditions in humic lakes are assumed to constrain littoral primaryproduction (PP), such that the littoral zone has been considered an insignificant contributor towhole-lake PP. However, that assumption is based on models and inferences from pelagic processeswhich do not take littoral zone structure into account. Many lakes have an extensive ring of aquaticvegetation lying near the water surface, which provides substratum for epiphytic algae under well-illuminated conditions.2. We measured both pelagic and littoral PP and community respiration (CR) in Mekkoj€arvi, a s…